System.Net.WebUtility.HtmlEncode C# (CSharp) Method

        public static string HtmlEncode(string value)
        {
            if (string.IsNullOrEmpty(value))
            {
                return value;
            }

            // Don't create StringBuilder if we don't have anything to encode
            int index = IndexOfHtmlEncodingChars(value, 0);
            if (index == -1)
            {
                return value;
            }

            StringBuilder sb = StringBuilderCache.Acquire(value.Length);
            HtmlEncode(value, index, sb);
            return StringBuilderCache.GetStringAndRelease(sb);
        }

        internal void FinishInitialization()
        {
            string host = UserHostName;

            if (_version > HttpVersion.Version10 && (host == null || host.Length == 0))
            {
                _context.ErrorMessage = "Invalid host name";
                return;
            }

            string path;
            Uri    raw_uri = null;

            if (MaybeUri(_raw_url.ToLowerInvariant()) && Uri.TryCreate(_raw_url, UriKind.Absolute, out raw_uri))
            {
                path = raw_uri.PathAndQuery;
            }
            else
            {
                path = _raw_url;
            }

            if ((host == null || host.Length == 0))
            {
                host = UserHostAddress;
            }

            if (raw_uri != null)
            {
                host = raw_uri.Host;
            }

            int colon = host.IndexOf(':');

            if (colon >= 0)
            {
                host = host.Substring(0, colon);
            }

            string base_uri = String.Format("{0}://{1}:{2}",
                                            (IsSecureConnection) ? "https" : "http",
                                            host, LocalEndPoint.Port);

            if (!Uri.TryCreate(base_uri + path, UriKind.Absolute, out _url))
            {
                _context.ErrorMessage = WebUtility.HtmlEncode("Invalid url: " + base_uri + path);
                return;
            }

            CreateQueryString(_url.Query);

            _url = HttpListenerRequestUriBuilder.GetRequestUri(_raw_url, _url.Scheme,
                                                               _url.Authority, _url.LocalPath, _url.Query);

            if (_version >= HttpVersion.Version11)
            {
                string t_encoding = Headers["Transfer-Encoding"];
                _is_chunked = (t_encoding != null && string.Equals(t_encoding, "chunked", StringComparison.OrdinalIgnoreCase));
                // 'identity' is not valid!
                if (t_encoding != null && !_is_chunked)
                {
                    _context.Connection.SendError(null, 501);
                    return;
                }
            }

            if (!_is_chunked && !_cl_set)
            {
                if (string.Equals(_method, "POST", StringComparison.OrdinalIgnoreCase) ||
                    string.Equals(_method, "PUT", StringComparison.OrdinalIgnoreCase))
                {
                    _context.Connection.SendError(null, 411);
                    return;
                }
            }

            if (String.Compare(Headers["Expect"], "100-continue", StringComparison.OrdinalIgnoreCase) == 0)
            {
                HttpResponseStream output = _context.Connection.GetResponseStream();
                output.InternalWrite(s_100continue, 0, s_100continue.Length);
            }
        }